1. Field of the Invention
The present invention is directed generally to gauges and, more particularly, to mechanical gauges.
2. Description of the Related Art
A mechanical pressure gauge can be used to measure pressure of a contained gas. Typically a pointer is used in the gauge to point to a particular pressure value demarcation on a dial face to indicate present pressure of the contained gas. A Bourdon tube can be used since it is constructed to assume a particular shape supported by pressurized gas inside the Bourdon tube. The Bourdon tube is gaseously coupled to the contained gas so is pressurized at the same pressure of the contained gas. If the pointer is mechanically coupled to the Bourdon tube so that movement of the pointer will properly indicate on the dial face pressure changes of the contained gas, then the pointer need only be positioned on the dial face according to one known pressure reading of the contained gas in order for the gauge to be calibrated and deemed accurate. Some gauges, conventionally known as dual gauges, use two Bourdon tubes each mechanically coupled to a separate pointer so that the two pointers of a dual gauge share a common dial face. Unfortunately, these conventional dual gauges are unable to provide a calibration function for both of their pointers.